1. Field of the Invention
The present invention relates generally to transmissions, and more particularly to an improvement of a flexible joint for a power transmission of the divided type.
2. Description of the Prior Art
Within certain power transmissions shafts, such as, for example, the propeller shaft of an automobile, the vibration of the drive system is transmitted by the shaft to the devices located downstream thereof, and a flexible joint is sometimes installed midway upon the power transmission shaft so as to prevent the transmission of such vibrations in order to avoid damage to the successive or downstream devices by means of such vibrations of the drive system or noise generated thereby through resonance thereof. An assembly of multi-split joint elements linked together is one example of such flexible joints.
Such a divided type flexible joint is constructed such that the bolt hole metal sleeves upon the drive side of the transmission, for holding the bolts with which to fix the flexible joint to the drive shaft, and the bolt hole metal sleeves disposed upon the driven side, for holding the bolts with which to fix the flexible joint to the driven shaft, are alternately arranged upon the circumference of the transmission, and the adjacent drive-side bolt-hole metal sleeves are linked together with joint elements which are wound with an endless elastic fiber or band and then enveloped with rubber or a synthetic resin.
When a torque is applied to the flexible joint of this type, the joint elements thus linked in a loop will alternately receive a tensile force and a compressive force, and consequently, the joint elements which are subjected to compression are likely to be locally deflected when the compressive force exceeds a predetermined limit, resulting in that the internal fiber or band becomes exposed due to rupture of the other components. Even when such excessive damage is not done, however, the joint elements which have been under compression may be exposed to tension forces under reverse operation conditions, and depending upon the ratio between normal and reverse operations, and upon the frequency of such operations, it may not always be ideal to have all of the joint elements conventionally built with the same shape and rigidity.